A bone researcher based in Japan with 10 retractions under his belt has retracted two more papers for similar reasons — problems with the underlying data, and including co-authors who didn’t participate in the project.

In both notices, Yoshihiro Sato is pegged as responsible for the content of the papers. The newly retracted research covers a long timespan — one paper was published in 2000, the other in 2013.

Here’s the first notice, issued by the Journal of Bone and Mineral Research:

The above article, published online on 1 December 2000 in Wiley Online Library (wileyonlinelibrary.com), and in Volume 15, Issue 12, pages 2487–2494, has been retracted by agreement between the authors, the Journal Editor in Chief, Juliet Compston, and Wiley Periodicals, Inc. The retraction has been agreed due to concerns about the underlying data to which the authors have given no satisfactory response. Dr Sato acknowledges that his co-authors are named as such for honorary reasons and are not responsible for the content of the manuscript.

Yoshihiro Sato, Yoshiaki Honda, Jun Iwamoto and Nobuko Amano wish to retract the above-cited article due to concern that data have been fabricated. Dr. Yoshihiro Sato was the only author responsible for study design, data collection, data analysis, interpretation of data, and drafting of the manuscript. Drs. Yoshiaki Honda, Jun Iwamoto and Nobuko Amano did not participate in study design, data collection, data analysis, interpretation of data, and drafting of the manuscript. Furthermore, the co-authors had not realized not only the misconduct but also the existence of this article before the article was published.

The 2013 paper has been cited once.

These follow a sweep of 10 retractions by multiple journals — including JAMA — of papers (and one letter) co-authored by Sato, who is based at Mitate Hospital in Japan.

The 2013 paper includes two authors who were listed in some of Sato’s other pulled papers: Yoshiaki Honda, and Jun Iwamoto, at Keio University School of Medicine, who is listed as a co-author on all of Sato’s retractions (except for the newly retracted 2000 paper).